Do dogs understand death? ?

[Jordan]

I have two dogs... Sugar and spice.. Augur is a Maltese/chiuahah and spice is a miniature dachshund. Spice died at the vet today and she was brought home in the box... Sugar was smelling the box, and Im sure she smelt that it was spice.. We buried her and we were all crying.. So my question is this... Does sugar know that spice Is dead? And would it be a good Idea to get a new dog for sugar to have a friend?